Advances in Nitrogen-Directed Aromatic Compound ortho-C—H Bond Borylation Catalyzed by Transition Metals

doi:10.6023/cjoc202103013

Abstract

Aromatic boron compounds have been widely used in synthetic chemistry, materials and medicinals, and developing new methods for their synthesis has been a hot topic. Directing groups assisted C—H bond borylation catalyzed by transition metal has significant advantages in step-economy, substrates diversity and high regio-selectivity. The borylation of nitrogen-based substrates has attracted interest from researchers, because four-coordinated organoboron compounds chelated by N,C are important photoelectric materials. In this paper, the preparation of aromatic boron compounds from ortho-C—H bond borylation catalyzed by Ir, Rh, Ru, Pd assisting by directing groups containing nitrogen atoms is summarized.

Key words: ortho-C—H activation, borylation, nitrogen-directed, transition metal catalyze

Cite this article

Huanhuan Luo, Na Pei, Jing Zhang. Advances in Nitrogen-Directed Aromatic Compound ortho-C—H Bond Borylation Catalyzed by Transition Metals[J]. Chinese Journal of Organic Chemistry, 2021, 41(8): 2990-3001.

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Fig. & Tab. 20

Scheme 1. Mechanism of C—H bond borylation of 2-arylpyridine catalyzed by iridium with hemilabile ligand

Scheme 2. Iridium catalyzed diborylation of N,N-dimethyl- hydrazones derivates

Scheme 3. Iridium catalyzed monoborylation of N,N-dimethyl- hydrazones derivates

Scheme 4. Iridium catalyzed borylation of N,N-dimethylben- zylamine derivates

Scheme 5. Iridium catalyzed outer-sphere directed C—H bond borylation

Scheme 6. Ligand-enabled iridium catalyzed selective ortho- and meta-C—H bond borylation

Scheme 7. Iridium catalyzed C—H bond borylation with Si-P bidentate ligand

Scheme 8. Iridium catalyzed C—H bond borylation with N-B bidentate ligand

Scheme 9. Iridium catalyzed asymmetric C—H borylation of diarylmethylamines

Scheme 10. Iridium catalyzed C—H borylation of 2-benzylpyridine

Scheme 11. Rhodium catalyzed borylation-amination of 2- aminobiaryl derivatives

Scheme 12. Rhodium catalyzed borylation of 2-pyridones

Scheme 13. Rhodium catalyzed borylation of 2-arylpyridine involved in carbene

Scheme 14. Carboxyalkyl-NHC-rhodium catalyzed borylation of 2-arylpyridine

Scheme 15. Mechanism of palladium catalyzed oxidative C—H bond borylation

Scheme 16. Mechanisms of palladium/free catalyzed C—H bond borylation of 2-phenyl pyridine

Scheme 17. Mechanisms of C—H bond borylation of 2-phenyl pyridine catalyzed by [RuH2(PPh3)(η5-3-phenylindenyl)(SiEt3)]

Scheme 18. Mechanism of C—H bond diborylation catalyzed by [RuH2(CO)(PPh3)3]

Scheme 19. C—H bond borylation of aromatic imines catalyzed by Ru(cod)(cot)

Scheme 20. Mechanism of C—H bond diborylation catalyzed by (iPrPOCOP)Ru

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